Pump piston



Nov. 24, 1931. B, E, T'YLER 1,833,343

PUMP PI STON Filed Feb. 15, 1950 Patented Nov. 24, 1931 UNITED STATESBERT E. TYLER, DE LOS ANGELES, CALIFORNIA PUMP PISTON Application filedFebruary 15, 1930. Serial No. 428,673.

This invention relates to pump pistons and is an improvement over myco-pending application bearing Serial No. 369,590, filed June 10, 1929.v

The object of this invention is to provide a piston constructed in sucha manner that the fluid pressure developed within the cylinder duringoperation of the pump will expand packers of the piston into engagementwith the liner or cylinder wall.

Another object of this invention is to provide a piston having resilientpacking rings held in place on the piston by metallic retaining membersin such a manner that the parts forming the piston may be easily andquickly assembled.

Other objects and advantages will be apparent from the followingdescription, refcrence being had to the accompanying drawings, in which:

Fig. 1 is a sectional view taken through a pump liner and the improvedpiston;

Fig. 2 is a front elevation of the packing;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 2;

Fig. 4 is an elevation of the packing;

Fig. 5 is an end view of the metallic retaining member;

Fig. 6 is a sectional view taken on line 66 of Fig. 5;

Fig. 7 is a perspective view'of the core of the piston.

Referring more specifically to the drawings, 10 designates a pump linerin which is slidably mounted a piston generally designated at 12.

The piston consists of an annular metallic core 14, a pair ofresilientpackers 16 and a pair of packing retaining members 18, theabove parts are adaptedto be placed together and mounted on a piston rod20 and are constructed as follows:

Referring to Figs. 2, 3, and 4 the packer 16 is shown as it appearsbefore insertion into the pump liner and is in the form of an annularbody of resilient material (preferably soft rubber) having a centrallydisposed opening 22, an annular peripheral flange 23 encircling a hub orinternal flange 24 and an annular boss 25 formed on its inner face, the50 .flange is expanded beyond its normal diamhaving an outside diameterslightly less than that of the internal diameter or bore of the pumpliner, each of its faces 36 being recessed as indicated at 37 and isprovided with a 5 centrally disposed opening 38 to receive the pistonrod 20.

Assembly of the piston is preferably done by first placing a packer oneach of the retaining members, then placing one of the 70 units thusassembled designated at 40 on the piston rod, it being noted that one ofthe retaining members is provided with a tapered .pening correspondingto the taper of the piston rod, the core is then placed on the rod andthe other unit of the packer and retaining member designated at 42 isplaced on the rod and a tightening nut 43. applied to the threaded endof the rod. Tightening of the nut draws the parts thus assembled intoengagement with the shoulder 45 formed on the piston rod.

The piston is adapted to be inserted into the liner or pump cylinder 10,the packers being compressed against the action of the rings 27 by asuitable tool. Referring to Fig. 1 it will be seen that the annular boss25 on the packers rest in the recess formed in the core 14 and that theannular flange on the retaining members extends into the peripheralspace between the flange 23 and hub or internal flange 24 of thepackers, thus retaining or holding the packer firmly in place thereon.

During operation of the pump the fluid pressure developed Within thecylinder on the power stroke will be exerted on the internal area of theflange of the packers and expand same into engagement with the linerwall due to the fluid Within the space between surface 46 of the flangeof the retaining member reacting upon the internal surface of the flangeof the packer.

Reaction of the fluid upon the outer face 4:9 and inner face 50 of thepackers Will force the same into tight engagement with the surface ofthe core, thereby-eflecting a fluid tight seal between the packers andcore. Any wear on the flanges of the packers will be taken up byexpansion of the split rings 27,

From the foregoing it will be seen that the piston above described is ofsimple and dur- 1 able construction, may be easily and quicklyassembled, and is practically leak-proof.

l. A pump'piston comprising an annular core having an annular recessformed in each of its flat faces, a pair of packers each of which havean annular boss resting in the an nular recesses formed in said core, apair'of Leashes second packer member of ring form provided with aperipheral and an internal flange, an apertured retaining member mountedon said rod, said member being provided in one of its faces with anannular recess, the internal retaining members having bosses extendinginto openings formed in said packers and engaging the surfaces of therecesses formed in said core, each of said retaining members having anannular flange encircling a hub formed on said packers, said packershaving annular flanges encircling the flanges on said retaining members,and a split expansion ring disposed in a groove formed in each of theannular flanges of said packers.

52. A pump piston comprising an annular core, a pair of packers abuttingthe end faces of said core, a pair of retaining members having bossesextending into openings formed in said packers and engaging the surfacesof the recesses formed in said core, each of said retaining membershaving an annular flange encirclinga hub formed on said packers, saidpackers having annular flanges encircling the flanges on said retainingmembers, and a split expans1on ring d1sposed in a groove formed ineachof the an-

